1 /*
2  * Copyright 2013, Michael Ellerman, IBM Corp.
3  * Licensed under GPLv2.
4  */
5 
6 #define _GNU_SOURCE
7 #include <unistd.h>
8 #include <sys/syscall.h>
9 #include <string.h>
10 #include <stdio.h>
11 #include <sys/ioctl.h>
12 
13 #include "event.h"
14 
15 
16 int perf_event_open(struct perf_event_attr *attr, pid_t pid, int cpu,
17 		int group_fd, unsigned long flags)
18 {
19 	return syscall(__NR_perf_event_open, attr, pid, cpu,
20 			   group_fd, flags);
21 }
22 
23 void event_init_opts(struct event *e, u64 config, int type, char *name)
24 {
25 	memset(e, 0, sizeof(*e));
26 
27 	e->name = name;
28 
29 	e->attr.type = type;
30 	e->attr.config = config;
31 	e->attr.size = sizeof(e->attr);
32 	/* This has to match the structure layout in the header */
33 	e->attr.read_format = PERF_FORMAT_TOTAL_TIME_ENABLED | \
34 				  PERF_FORMAT_TOTAL_TIME_RUNNING;
35 }
36 
37 void event_init_named(struct event *e, u64 config, char *name)
38 {
39 	event_init_opts(e, config, PERF_TYPE_RAW, name);
40 }
41 
42 #define PERF_CURRENT_PID	0
43 #define PERF_NO_CPU		-1
44 #define PERF_NO_GROUP		-1
45 
46 int event_open_with_options(struct event *e, pid_t pid, int cpu, int group_fd)
47 {
48 	e->fd = perf_event_open(&e->attr, pid, cpu, group_fd, 0);
49 	if (e->fd == -1) {
50 		perror("perf_event_open");
51 		return -1;
52 	}
53 
54 	return 0;
55 }
56 
57 int event_open_with_group(struct event *e, int group_fd)
58 {
59 	return event_open_with_options(e, PERF_CURRENT_PID, PERF_NO_CPU, group_fd);
60 }
61 
62 int event_open(struct event *e)
63 {
64 	return event_open_with_options(e, PERF_CURRENT_PID, PERF_NO_CPU, PERF_NO_GROUP);
65 }
66 
67 void event_close(struct event *e)
68 {
69 	close(e->fd);
70 }
71 
72 int event_reset(struct event *e)
73 {
74 	return ioctl(e->fd, PERF_EVENT_IOC_RESET);
75 }
76 
77 int event_read(struct event *e)
78 {
79 	int rc;
80 
81 	rc = read(e->fd, &e->result, sizeof(e->result));
82 	if (rc != sizeof(e->result)) {
83 		fprintf(stderr, "read error on event %p!\n", e);
84 		return -1;
85 	}
86 
87 	return 0;
88 }
89 
90 void event_report_justified(struct event *e, int name_width, int result_width)
91 {
92 	printf("%*s: result %*llu ", name_width, e->name, result_width,
93 	       e->result.value);
94 
95 	if (e->result.running == e->result.enabled)
96 		printf("running/enabled %llu\n", e->result.running);
97 	else
98 		printf("running %llu enabled %llu\n", e->result.running,
99 			e->result.enabled);
100 }
101 
102 void event_report(struct event *e)
103 {
104 	event_report_justified(e, 0, 0);
105 }
106